Engine starting device



May 4, 1937. N. HERZMARK ENGINE STARTING DEVICE Original Filed Feb 4, l93l -Patented May 4, i t e t i UNITED "STATES PATENT OFFICE i f 2 079 1 I t t I 1 'ENGINEJSTARTINQY Device l t t H Nicolas flerzfmarh laris, France I a original assassin February i;1931,-Serial so. a

513,437. Patent ,No. 2,035,161. Divided and this applicationNovemher 1, 1935, Serial No. p 47,858. In France February l, 1930,

, t n t 40laims. (Cl.-121--- 37) a t a a i a i This invention relates to fluid pressure operated started is fitted with acoupling member g havstarters forginternal combustion uengines iand ing ratchet jaws and coming into engagement, at t other motors, o f the type comprising two pistons the time of starting, withthe'corresponding memlocated in a iixed cylinder formed by the casing ber g keyed upon the shaft of the said engine. )5 of the starter andubetween which pistons the L'Ihese screwthreadedmembers e andlg are 5 normally (1. e. when in the inoperative position) compressed airor gas is admitted. The present invention (which forms a division telescoped one vwithinthe other. The nut f is at of my pending application Serial No..513,43'7, filed the end of the sleeve e opposite to the nut l7. p February 4, 1931 and issued as Patent No. Itwill, also benoted. that the outersleeveeds 2,035,161 on March 24, 1936) has for its main directly attached to piston is whilst the inner 10 t object to reduce the size or bulk of ,the starter, sleeve g is directly attached to the piston d, i

or for'the sam e size to increase .themaximum A,te"nsion spring h, connecting the inner end number oiturns which thestarter can make in a of thesleev eg with the outer end of the sleeve e, single starting operation, is intended to bring back the pistons c and d suba The invention also comprises a particular arstantially'into contact afterlthe operative stroke 15 rangernent ofthe starter permitting its interior of the starter, in order to restore the partsto the parts to be easily withdrawn fromthe casing, with i positionior another operation, As shown in the a a view to their inspection, or replacement, withdrawing, theedge ofa flanged formed on the "out it being necessary to take down, the pipes piston d abuts directly against the "screw- 2 connecting thestarter withthe reservoir of comthreaded bossof theljpiston cto limit the return pressedair orYother fluid'ujnder pressuref f, l i 1 movement and thus ensure maintenance of a pre- The invention has fora further object to endetermined spacing'betweenthe pistons for the sure the acc ate positioning of: the" pistons, admission of pressure fluid.

when they are automatically drawntoeetheriafter A pipe connection'i leading to the fluid pre's-.

the operativefstroke of the1startergi n readiness sure (such as compressed air) supply line is de- 5 for the next operative stroke. t I i signed to admit the fluidunder pressure into the i One form of carrying out the present invericasing'or cylinder aat apoint between the two tion, given solely by wayflof example ishere pistons c and d. Asuitable cock or valve (not aft rdescri edw th reference to the a c mp nyshown) controls the admission of the compressed 5 ingdrawing', which is a longitudinal axial section air orfluid into pipe connection 1'.

of a preferred construction. In this drawing, the Anumber of balls a are spring-pushed against casing q of the starter is fixed byany suitable the"0111:1-Sfililll'lgS7" formed onthe exterior surmeans as ,by bolts Knot shown) upon the engine race of the sleeve e, so that this sleeve and conseor upon the cha'ssisfsupporting the engine. The quently the piston 0, will experience a certain recasing 4 is provided atits front end (remote from sistance to their axial displacement at the be- 35 the engine) with an annular member b of which ginning of such movement.

, the interior surface b is screw-threaded."*In'the The working of the arrangement is the] interior ofjthe casing a, which iorms the fixed fo1lowing: M i i i a l cylinder to which the air is admitted, are two When compressed air or gas is admitted between i pistons c and d, fitted with packing leathers c the two pistons c d by the appropriate operation 40 fandcl or similar elastic packing members, held of the aforesaid cock or valve, the piston d, in position byrringsc and d secured by screws-c which is entirely free, is displaced towards the and d The piston @whichisthe driving piston, member y the sleeve g, with which piston-d is is fast with a socket or sleeve e, the exterior "sur- *fast, screws throughthe nut I which for the mo- 945 face e of which isfscrew-threaded in such a mentis stationary. The jaw coupling g 'comes mannerastobe ableto scre'w'through the aninto'engagement withthe coupling 9 and the" l nular 'rnember b. This member: b forms a piston dis thereupon stopped. a y quick-fpitch nut. The other end of-the sleeve e Under thefor ce derived from the compressed is also provldedon its interior face with a nut air acting onthe piston c,the balls 7' are now t 1=b The {other piston d; which is displacea'ble pushed back out of the cups i and the driving 50 c through only a limited stroke, is fixed by means piston c moves axially whilst revolving as the of a circularhnut 11? upon an inner socket or sleeve e screws through the nut formed by the sleeve 9, aIsoScreW-threaded onits exterior surmember I At the same-time, the nut f, fast with face 9 and adapted'to screw through the nut f. the travelling and revolving sleeve e, causes the t The end of'sleeve g adjacent to the engine to be screw-threaded sleeve 9 to turn, which conse- 55 quently imparts a movement of rotation to the coupling members a and g and thence to the motor shaft.

It will be seen that when the sleeve e has made one complete turn and has consequently advanced one screw-pitch, the interior sleeve 9 has also performed one complete revolution relatively to the sleeve e and therefore has made two complete turns relatively to the fixed part b. This obviously is on condition that the screw threads of the two sleeves e and g are of equal pitch but of opposite hand or direction. The, result of this arrangement is that the number of turns of the central sleeve 9 and therefore of the shaft to be started, is double that which would be obtained with a single screw-threaded sleeve.

It will be noted that the movement of driving piston c away from piston d applies driving torque to the engine to be started. It is also to be noted that the pistons c d move in opposite directions when compressed air has been admitted, at i and that both these pistons are guided by the bore of 'the cylinder casing a. After the engine has been started, the fluid pressure is relieved and thespring It returns the parts to their normal positions. a

' In order to provide for dismounting the starter without having to disconnect the compressed air pipes, theinner cylinder head I of the starter is fixed to the cylinder a by screws or the like m entering a groove n, and the outer end or annular member b is screwed into the said cylinder. Consequently, whenit is desired to withdraw from the cylinder or casing all the components of the starter, it is sufficient to unscrew the screws m and the annular member b.

Instead of compressed air to separate the pistons, I may employ gas under pressure, and such gas, may be obtained from a storage tank or directly-from an explosion (such as that of a cartridge) conveyed into the inlet i.

The invention is not limited to the form of construction which has been described but can be carried out with all modifications based on the same principle. The starter can likewise be combined with an air compressor mounted on the same axis and driven by the motor shaft. For this purpose, the rear end of the starter casing or cylinder barrel (1, as shown in the drawing, is provided with a centering portion or register 1 in which the extremity of the compressor casing can be located in alinement with the starter and the engine shaft.

. What I claim is:--

1. An engine starter comprising a fixed cylindrical casing; a stationary apertured closure member at one end of said casing, the walls defining said aperture being threaded; an end plate slidable throughout the length of said casing and adapted normally to close the other end of said casing; a pair of opposed pistons of equal diameter and reciprocable within said casingpmeans for introducing fluid under pressure between the pistons to move the pistons in opposite directions towards the apertured closure member and the end plate respectively; an outer sleeve-within said cylindrical casing having external and in ternal threads, the external threads adapted to engage the threads of the stationary apertured closure member and to be rotated thereby, said sleeve being directly connected to one of said pis tons and being protrusible in part from said casing through the apertured closure member; an inner sleeve within the outer sleeve having threads to engage the internal threads of the outer sleeve to be rotated thereby, said inner sleeve being secured directly to the other of said pistons; and a clutch element secured to one end of the inner sleeve and engageable with a clutch element of the engine to be started, whereby the rotation of said sleeves is imparted to the engine, the screw-threaded portion of said inner sleeve being normally within the length of the outer sleeve.

2. In an engine starter, a fixed cylindrical casing, a pair of pistons of equal diameter slidable I in said casing, means for admitting pressure fiuid between said pistons to'move them in opposite directions, a screw-threaded sleeve secured to one of said pistons, a stationary nut co-operating with said sleeve at one end of said casing, an apertured end plate slidable throughout the length of said casing and adapted normally to close the other end of said casing, an inner sleeve secured to the other of said pistons, said inner sleeve having screw engagement with the first mentioned sleeve for rotating said inner sleeve by movement of the first mentioned sleeve, and means secured to said inner sleeve for engaging an engine shaft.

3. In an engine starter, a fixed cylindrical casing, a stationary apertured closure member at one endof said casing, the walls defining theaperture being threaded, an apertured end plate slidable throughout the length of said casing and adapted normally to close the other end of said casing, a pair of pistons of equal diameter slidable in said casing, means for admitting pressure fiuid between said pistons to separate them by movement in opposite directions, an internally and externally screw-threaded sleeve secured to one of said pistons, said sleeve adapted to screw its external threads through the threaded aperture in said closure member, an inner sleeve secured to the other ofsaid pistons, said inner sleeve having external screw threads co-operating with the internal threads of the first mentioned sleeve for rotating said inner sleeve by movement oi the first mentioned sleeve, and means secured to said inner sleeve for engaging an engine shaft, said inner sleeve having limited axial movement through the aperture in said end plate.

4. In an engine starter, a fixed cylindrical casing, a pair of pistons of equal diameter slidable in said casing, means for admitting pressure fiuid between said pistons to move them in opposite directions, a screw-threaded sleeve secured to one of said pistons, a stationary nut cooperating with said sleeve at one end of said casing, an apertured end plate slidable throughout the length of said casing and adapted normally to close the other end of said casing, an inner sleeve secured to the other of said pistons, a nut holding said other piston upon said inner sleeve, said nut extending outside the aperture in said end plate, means for rotating said inner sleeve by movement of the firstmentioned sleeve, and means secured to said inner sleeve for engaging an engine shaft, the return movement of said pistons after completion of a starting operation being limitedby the abutment of said nut with said end plate and. by the abutment of said pistons against one another.

' NICOLAS HERZMARK. 

